Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Disabled |
Yes |
Yes |
1.16 |
- |
Checks that left braces for adjacent single line lets are aligned.
# bad
let(:foobar) { blahblah }
let(:baz) { bar }
let(:a) { b }
# good
let(:foobar) { blahblah }
let(:baz) { bar }
let(:a) { b }
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Disabled |
Yes |
Yes |
1.16 |
- |
Checks that right braces for adjacent single line lets are aligned.
# bad
let(:foobar) { blahblah }
let(:baz) { bar }
let(:a) { b }
# good
let(:foobar) { blahblah }
let(:baz) { bar }
let(:a) { b }
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.4 |
- |
Check that instances are not being stubbed globally.
Prefer instance doubles over stubbing any instance of a class
# bad
describe MyClass do
before { allow_any_instance_of(MyClass).to receive(:foo) }
end
# good
describe MyClass do
let(:my_instance) { instance_double(MyClass) }
before do
allow(MyClass).to receive(:new).and_return(my_instance)
allow(my_instance).to receive(:foo)
end
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.11 |
- |
Checks that around blocks actually run the test.
# bad
around do
some_method
end
around do |test|
some_method
end
# good
around do |test|
some_method
test.call
end
around do |test|
some_method
test.run
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.25 |
- |
Check for expectations where be
is used without argument.
The be
matcher is too generic, as it pass on everything that is not
nil or false. If that is the exact intend, use be_truthy
. In all other
cases it’s better to specify what exactly is the expected value.
# bad
expect(foo).to be
# good
expect(foo).to be_truthy
expect(foo).to be 1.0
expect(foo).to be(true)
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
Yes |
2.20 |
- |
Prefer using be_empty
when checking for an empty array.
# bad
expect(array).to contain_exactly
expect(array).to match_array([])
# good
expect(array).to be_empty
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
No |
Yes (Unsafe) |
2.9.0 |
2.16 |
Check for expectations where be(…)
can replace eq(…)
.
The be
matcher compares by identity while the eq
matcher compares
using ==
. Booleans and nil can be compared by identity and therefore
the be
matcher is preferable as it is a more strict test.
# bad
expect(foo).to eq(true)
expect(foo).to eq(false)
expect(foo).to eq(nil)
# good
expect(foo).to be(true)
expect(foo).to be(false)
expect(foo).to be(nil)
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
No |
Yes (Unsafe) |
1.7 |
2.16 |
Check for expectations where be(…)
can replace eql(…)
.
The be
matcher compares by identity while the eql
matcher
compares using eql?
. Integers, floats, booleans, symbols, and nil
can be compared by identity and therefore the be
matcher is
preferable as it is a more strict test.
This cop only looks for instances of expect(…).to eql(…)
. We
do not check to_not
or not_to
since !eql?
is more strict
than !equal?
. We also do not try to flag eq
because if
a == b
, and b
is comparable by identity, a
is still not
necessarily the same type as b
since the #==
operator can
coerce objects for comparison.
# bad
expect(foo).to eql(1)
expect(foo).to eql(1.0)
expect(foo).to eql(true)
expect(foo).to eql(false)
expect(foo).to eql(:bar)
expect(foo).to eql(nil)
# good
expect(foo).to be(1)
expect(foo).to be(1.0)
expect(foo).to be(true)
expect(foo).to be(false)
expect(foo).to be(:bar)
expect(foo).to be(nil)
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
Yes |
2.9.0 |
2.10.0 |
Ensures a consistent style is used when matching nil
.
You can either use the more specific be_nil
matcher, or the more
generic be
matcher with a nil
argument.
This cop can be configured using the EnforcedStyle
option
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.12 |
2.23 |
Check that before/after(:all) isn’t being used.
# bad
#
# Faster but risk of state leaking between examples
#
describe MyClass do
before(:all) { Widget.create }
after(:all) { Widget.delete_all }
end
# good
#
# Slower but examples are properly isolated
#
describe MyClass do
before(:each) { Widget.create }
after(:each) { Widget.delete_all }
end
Name | Default value | Configurable values |
---|---|---|
Exclude |
|
Array |
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
Yes |
2.11 |
2.14 |
Prefer negated matchers over to change.by(0)
.
In the case of composite expectations, cop suggest using the
negation matchers of RSpec::Matchers#change
.
By default the cop does not support autocorrect of
compound expectations, but if you set the
negated matcher for change
, e.g. not_change
with
the NegatedMatcher
option, the cop will perform the autocorrection.
# bad
expect { run }.to change(Foo, :bar).by(0)
expect { run }.to change { Foo.bar }.by(0)
# bad - compound expectations (does not support autocorrection)
expect { run }
.to change(Foo, :bar).by(0)
.and change(Foo, :baz).by(0)
expect { run }
.to change { Foo.bar }.by(0)
.and change { Foo.baz }.by(0)
# good
expect { run }.not_to change(Foo, :bar)
expect { run }.not_to change { Foo.bar }
# good - compound expectations
define_negated_matcher :not_change, :change
expect { run }
.to not_change(Foo, :bar)
.and not_change(Foo, :baz)
expect { run }
.to not_change { Foo.bar }
.and not_change { Foo.baz }
# bad (support autocorrection to good case)
expect { run }
.to change(Foo, :bar).by(0)
.and change(Foo, :baz).by(0)
expect { run }
.to change { Foo.bar }.by(0)
.and change { Foo.baz }.by(0)
# good
define_negated_matcher :not_change, :change
expect { run }
.to not_change(Foo, :bar)
.and not_change(Foo, :baz)
expect { run }
.to not_change { Foo.bar }
.and not_change { Foo.baz }
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
Yes |
2.13 |
- |
Enforces consistent use of be_a
or be_kind_of
.
# bad
expect(object).to be_kind_of(String)
expect(object).to be_a_kind_of(String)
# good
expect(object).to be_a(String)
expect(object).to be_an(String)
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
Yes |
2.19 |
- |
Checks where contain_exactly
is used.
This cop checks for the following:
- Prefer match_array
when matching array values.
- Prefer be_empty
when using contain_exactly
with no arguments.
# bad
it { is_expected.to contain_exactly(*array1, *array2) }
# good
it { is_expected.to match_array(array1 + array2) }
# good
it { is_expected.to contain_exactly(content, *array) }
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.36 |
- |
context
should not be used for specifying methods.
# bad
context '#foo_bar' do
# ...
end
context '.foo_bar' do
# ...
end
# good
describe '#foo_bar' do
# ...
end
describe '.foo_bar' do
# ...
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.20 |
2.13 |
Checks that context
docstring starts with an allowed prefix.
The default list of prefixes is minimal. Users are encouraged to tailor
the configuration to meet project needs. Other acceptable prefixes may
include if
, unless
, for
, before
, after
, or during
.
They may consist of multiple words if desired.
This cop can be customized allowed context description pattern
with AllowedPatterns
. By default, there are no checking by pattern.
# .rubocop.yml
# RSpec/ContextWording:
# Prefixes:
# - when
# - with
# - without
# - if
# - unless
# - for
# bad
context 'the display name not present' do
# ...
end
# good
context 'when the display name is not present' do
# ...
end
Name | Default value | Configurable values |
---|---|---|
Prefixes |
|
Array |
AllowedPatterns |
|
Array |
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.0 |
2.7 |
Check that the first argument to the top-level describe is a constant.
It can be configured to ignore strings when certain metadata is passed.
Ignores Rails and Aruba type
metadata by default.
# .rubocop.yml
# RSpec/DescribeClass:
# IgnoredMetadata:
# type:
# - request
# - controller
# bad
describe 'Do something' do
end
# good
describe TestedClass do
subject { described_class }
end
describe 'TestedClass::VERSION' do
subject { Object.const_get(self.class.description) }
end
describe "A feature example", type: :feature do
end
Name | Default value | Configurable values |
---|---|---|
Exclude |
|
Array |
IgnoredMetadata |
|
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.0 |
- |
Checks that the second argument to describe
specifies a method.
# bad
describe MyClass, 'do something' do
end
# good
describe MyClass, '#my_instance_method' do
end
describe MyClass, '.my_class_method' do
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.15 |
- |
Avoid describing symbols.
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes (Unsafe) |
1.0 |
1.11 |
Checks that tests use described_class
.
If the first argument of describe is a class, the class is exposed to each example via described_class.
This cop can be configured using the EnforcedStyle
and SkipBlocks
options.
There’s a known caveat with rspec-rails’s controller
helper that
runs its block in a different context, and described_class
is not
available to it. SkipBlocks
option excludes detection in all
non-RSpec related blocks.
To narrow down this setting to only a specific directory, it is possible to use an overriding configuration file local to that directory.
# bad
describe MyClass do
subject { MyClass.do_something }
end
# good
describe MyClass do
subject { described_class.do_something }
end
# bad
describe MyClass do
subject { described_class.do_something }
end
# good
describe MyClass do
subject { MyClass.do_something }
end
Name | Default value | Configurable values |
---|---|---|
SkipBlocks |
|
Boolean |
EnforcedStyle |
|
|
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Disabled |
Yes |
No |
1.37 |
- |
Avoid opening modules and defining specs within them.
# bad
module MyModule
RSpec.describe MyClass do
# ...
end
end
# good
RSpec.describe MyModule::MyClass do
# ...
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Disabled |
Yes |
Yes |
1.33 |
- |
Enforces custom RSpec dialects.
A dialect can be based on the following RSpec methods:
-
describe, context, feature, example_group
-
xdescribe, xcontext, xfeature
-
fdescribe, fcontext, ffeature
-
shared_examples, shared_examples_for, shared_context
-
it, specify, example, scenario, its
-
fit, fspecify, fexample, fscenario, focus
-
xit, xspecify, xexample, xscenario, skip
-
pending
-
prepend_before, before, append_before,
-
around
-
prepend_after, after, append_after
-
let, let!
-
subject, subject!
-
expect, is_expected, expect_any_instance_of
By default all of the RSpec methods and aliases are allowed. By setting a config like:
RSpec/Dialect: PreferredMethods: context: describe
You can expect the following behavior:
# bad
context 'display name presence' do
# ...
end
# good
describe 'display name presence' do
# ...
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
Yes |
2.16 |
- |
Avoid duplicated metadata.
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes (Unsafe) |
1.7 |
2.13 |
Checks if an example group does not include any tests.
# bad
describe Bacon do
let(:bacon) { Bacon.new(chunkiness) }
let(:chunkiness) { false }
context 'extra chunky' do # flagged by rubocop
let(:chunkiness) { true }
end
it 'is chunky' do
expect(bacon.chunky?).to be_truthy
end
end
# good
describe Bacon do
let(:bacon) { Bacon.new(chunkiness) }
let(:chunkiness) { false }
it 'is chunky' do
expect(bacon.chunky?).to be_truthy
end
end
# good
describe Bacon do
pending 'will add tests later'
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.39 |
- |
Checks for empty before and after hooks.
# bad
before {}
after do; end
before(:all) do
end
after(:all) { }
# good
before { create_users }
after do
cleanup_users
end
before(:all) do
create_feed
end
after(:all) { cleanup_feed }
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.36 |
- |
Checks if there is an empty line after example blocks.
# bad
RSpec.describe Foo do
it 'does this' do
end
it 'does that' do
end
end
# good
RSpec.describe Foo do
it 'does this' do
end
it 'does that' do
end
end
# fair - it's ok to have non-separated one-liners
RSpec.describe Foo do
it { one }
it { two }
end
Name | Default value | Configurable values |
---|---|---|
AllowConsecutiveOneLiners |
|
Boolean |
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.27 |
- |
Checks if there is an empty line after example group blocks.
# bad
RSpec.describe Foo do
describe '#bar' do
end
describe '#baz' do
end
end
# good
RSpec.describe Foo do
describe '#bar' do
end
describe '#baz' do
end
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.14 |
- |
Checks if there is an empty line after the last let block.
# bad
let(:foo) { bar }
let(:something) { other }
it { does_something }
# good
let(:foo) { bar }
let(:something) { other }
it { does_something }
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.27 |
2.13 |
Checks if there is an empty line after hook blocks.
AllowConsecutiveOneLiners
configures whether adjacent
one-line definitions are considered an offense.
# bad
before { do_something }
it { does_something }
# bad
after { do_something }
it { does_something }
# bad
around { |test| test.run }
it { does_something }
# good
after { do_something }
it { does_something }
# fair - it's ok to have non-separated one-liners hooks
around { |test| test.run }
after { do_something }
it { does_something }
Name | Default value | Configurable values |
---|---|---|
AllowConsecutiveOneLiners |
|
Boolean |
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.14 |
- |
Checks if there is an empty line after subject block.
# bad
subject(:obj) { described_class }
let(:foo) { bar }
# good
subject(:obj) { described_class }
let(:foo) { bar }
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
Yes |
2.24 |
- |
Avoid empty metadata hash.
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
Yes |
2.24 |
- |
Use eq
instead of be ==
to compare objects.
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.5 |
2.3 |
Checks for long examples.
A long example is usually more difficult to understand. Consider
extracting out some behavior, e.g. with a let
block, or a helper
method.
You can set literals you want to fold with CountAsOne
.
Available are: 'array', 'hash', and 'heredoc'. Each literal
will be counted as one line regardless of its actual size.
# bad
it do
service = described_class.new
more_setup
more_setup
result = service.call
expect(result).to be(true)
end
# good
it do
service = described_class.new
result = service.call
expect(result).to be(true)
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.22 |
- |
Checks for examples without a description.
RSpec allows for auto-generated example descriptions when there is no description provided or the description is an empty one.
This cop removes empty descriptions. It also defines whether auto-generated description is allowed, based on the configured style.
This cop can be configured using the EnforcedStyle
option
# bad
it('') { is_expected.to be_good }
it '' do
result = service.call
expect(result).to be(true)
end
# good
it { is_expected.to be_good }
it do
result = service.call
expect(result).to be(true)
end
# bad
it('') { is_expected.to be_good }
it do
result = service.call
expect(result).to be(true)
end
# good
it { is_expected.to be_good }
Name | Default value | Configurable values |
---|---|---|
EnforcedStyle |
|
|
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.0 |
2.13 |
Checks for common mistakes in example descriptions.
This cop will correct docstrings that begin with 'should' and 'it'. This cop will also look for insufficient examples and call them out.
The autocorrect is experimental - use with care! It can be configured with CustomTransform (e.g. have ⇒ has) and IgnoredWords (e.g. only).
Use the DisallowedExamples setting to prevent unclear or insufficient descriptions. Please note that this config will not be treated as case sensitive.
# bad
it 'should find nothing' do
end
# good
it 'finds nothing' do
end
# bad
it 'it does things' do
end
# good
it 'does things' do
end
Name | Default value | Configurable values |
---|---|---|
CustomTransform |
|
|
IgnoredWords |
|
Array |
DisallowedExamples |
|
Array |
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
Yes |
2.5 |
- |
Checks for excessive whitespace in example descriptions.
# bad
it ' has excessive spacing ' do
end
# good
it 'has excessive spacing' do
end
# bad
context ' when a condition is met ' do
end
# good
context 'when a condition is met' do
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.7 |
2.23 |
Checks for expect(…)
calls containing literal values.
Autocorrection is performed when the expected is not a literal.
# bad
expect(5).to eq(price)
expect(/foo/).to eq(pattern)
expect("John").to eq(name)
# good
expect(price).to eq(5)
expect(pattern).to eq(/foo/)
expect(name).to eq("John")
# bad (not supported autocorrection)
expect(false).to eq(true)
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes (Unsafe) |
1.22 |
2.5 |
Checks for consistent style of change matcher.
Enforces either passing object and attribute as arguments to the matcher or passing a block that reads the attribute value.
This cop can be configured using the EnforcedStyle
option.
# bad
expect { run }.to change { Foo.bar }
expect { run }.to change { foo.baz }
# good
expect { run }.to change(Foo, :bar)
expect { run }.to change(foo, :baz)
# also good when there are arguments or chained method calls
expect { run }.to change { Foo.bar(:count) }
expect { run }.to change { user.reload.name }
Name | Default value | Configurable values |
---|---|---|
EnforcedStyle |
|
|
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.16 |
- |
Do not use expect
in hooks such as before
.
# bad
before do
expect(something).to eq 'foo'
end
# bad
after do
expect_any_instance_of(Something).to receive(:foo)
end
# good
it do
expect(something).to eq 'foo'
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.10 |
- |
Checks for opportunities to use expect { … }.to output
.
# bad
$stdout = StringIO.new
my_app.print_report
$stdout = STDOUT
expect($stdout.string).to eq('Hello World')
# good
expect { my_app.print_report }.to output('Hello World').to_stdout
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Disabled |
Yes |
No |
1.2 |
2.24 |
Checks that spec file paths are consistent and well-formed.
By default, this checks that spec file paths are consistent with the test subject and enforces that it reflects the described class/module and its optionally called out method.
With the configuration option IgnoreMethods
the called out method will
be ignored when determining the enforced path.
With the configuration option CustomTransform
modules or classes can
be specified that should not as usual be transformed from CamelCase to
snake_case (e.g. 'RuboCop' ⇒ 'rubocop' ).
With the configuration option SpecSuffixOnly
test files will only
be checked to ensure they end in '_spec.rb'. This option disables
checking for consistency in the test subject or test methods.
# bad
whatever_spec.rb # describe MyClass
# bad
my_class_spec.rb # describe MyClass, '#method'
# good
my_class_spec.rb # describe MyClass
# good
my_class_method_spec.rb # describe MyClass, '#method'
# good
my_class/method_spec.rb # describe MyClass, '#method'
# bad
whatever_spec.rb # describe MyClass
# good
my_class_spec.rb # describe MyClass
# good
my_class_spec.rb # describe MyClass, '#method'
Name | Default value | Configurable values |
---|---|---|
Include |
|
Array |
CustomTransform |
|
|
IgnoreMethods |
|
Boolean |
SpecSuffixOnly |
|
Boolean |
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.5 |
2.1 |
Checks if examples are focused.
This cop does not support autocorrection in some cases.
# bad
describe MyClass, focus: true do
end
describe MyClass, :focus do
end
fdescribe MyClass do
end
# good
describe MyClass do
end
# bad
fdescribe 'test' do; end
# good
describe 'test' do; end
# bad
fdescribe 'test' do; end
# good
describe 'test' do; end
# bad
shared_examples 'test', focus: true do; end
# good
shared_examples 'test' do; end
# bad
shared_context 'test', focus: true do; end
# good
shared_context 'test' do; end
# bad (does not support autocorrection)
focus 'test' do; end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.7 |
- |
Checks the arguments passed to before
, around
, and after
.
This cop checks for consistent style when specifying RSpec hooks which run for each example. There are three supported styles: "implicit", "each", and "example." All styles have the same behavior.
# bad
before(:each) do
# ...
end
# bad
before(:example) do
# ...
end
# good
before do
# ...
end
# bad
before(:example) do
# ...
end
# bad
before do
# ...
end
# good
before(:each) do
# ...
end
Name | Default value | Configurable values |
---|---|---|
EnforcedStyle |
|
|
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.29 |
- |
Checks for before/around/after hooks that come after an example.
# bad
it 'checks what foo does' do
expect(foo).to be
end
before { prepare }
after { clean_up }
# good
before { prepare }
after { clean_up }
it 'checks what foo does' do
expect(foo).to be
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
No |
2.4 |
- |
Checks for equality assertions with identical expressions on both sides.
# bad
expect(foo.bar).to eq(foo.bar)
expect(foo.bar).to eql(foo.bar)
# good
expect(foo.bar).to eq(2)
expect(foo.bar).to eql(2)
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.35 |
- |
Check that implicit block expectation syntax is not used.
Prefer using explicit block expectations.
# bad
subject { -> { do_something } }
it { is_expected.to change(something).to(new_value) }
# good
it 'changes something to a new value' do
expect { do_something }.to change(something).to(new_value)
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.8 |
- |
Check that a consistent implicit expectation style is used.
This cop can be configured using the EnforcedStyle
option
and supports the --auto-gen-config
flag.
# bad
it { should be_truthy }
# good
it { is_expected.to be_truthy }
Name | Default value | Configurable values |
---|---|---|
EnforcedStyle |
|
|
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.29 |
2.13 |
Checks for usage of implicit subject (is_expected
/ should
).
This cop can be configured using the EnforcedStyle
option
# bad
it do
is_expected.to be_truthy
end
# good
it { is_expected.to be_truthy }
it do
expect(subject).to be_truthy
end
# bad
it do
foo = 1
is_expected.to be_truthy
end
# good
it do
foo = 1
expect(subject).to be_truthy
end
it do
is_expected.to be_truthy
end
# bad
it { is_expected.to be_truthy }
# good
it { expect(subject).to be_truthy }
Name | Default value | Configurable values |
---|---|---|
EnforcedStyle |
|
|
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
No |
2.20 |
2.23 |
Do not set up test data using indexes (e.g., item_1
, item_2
).
It makes reading the test harder because it’s not clear what exactly is tested by this particular example.
The configurable options AllowedIdentifiers
and AllowedPatterns
will also read those set in Naming/VariableNumber
.
# bad
let(:item_1) { create(:item) }
let(:item_2) { create(:item) }
let(:item1) { create(:item) }
let(:item2) { create(:item) }
# good
let(:visible_item) { create(:item, visible: true) }
let(:invisible_item) { create(:item, visible: false) }
# bad
let(:item_1) { create(:item) }
let(:item_2) { create(:item) }
let(:item_3) { create(:item) }
# good
let(:item_1) { create(:item) }
let(:item_2) { create(:item) }
# good
let(:item_1) { create(:item) }
let(:item_2) { create(:item) }
Name | Default value | Configurable values |
---|---|---|
Max |
|
Integer |
AllowedIdentifiers |
|
Array |
AllowedPatterns |
|
Array |
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.12 |
- |
Checks for instance_double
used with have_received
.
# bad
it do
foo = instance_double(Foo).as_null_object
expect(foo).to have_received(:bar)
end
# good
it do
foo = instance_spy(Foo)
expect(foo).to have_received(:bar)
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.0 |
1.7 |
Checks for instance variable usage in specs.
This cop can be configured with the option AssignmentOnly
which
will configure the cop to only register offenses on instance
variable usage if the instance variable is also assigned within
the spec
# bad
describe MyClass do
before { @foo = [] }
it { expect(@foo).to be_empty }
end
# good
describe MyClass do
let(:foo) { [] }
it { expect(foo).to be_empty }
end
# rubocop.yml
# RSpec/InstanceVariable:
# AssignmentOnly: false
# bad
describe MyClass do
before { @foo = [] }
it { expect(@foo).to be_empty }
end
# allowed
describe MyClass do
it { expect(@foo).to be_empty }
end
# good
describe MyClass do
let(:foo) { [] }
it { expect(foo).to be_empty }
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.13 |
- |
Checks that only one it_behaves_like
style is used.
# bad
it_should_behave_like 'a foo'
# good
it_behaves_like 'a foo'
Name | Default value | Configurable values |
---|---|---|
EnforcedStyle |
|
|
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.14 |
- |
Check that all
matcher is used instead of iterating over an array.
# bad
it 'validates users' do
[user1, user2, user3].each { |user| expect(user).to be_valid }
end
# good
it 'validates users' do
expect([user1, user2, user3]).to all(be_valid)
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.7 |
1.14 |
Enforce that subject is the first definition in the test.
# bad
let(:params) { blah }
subject { described_class.new(params) }
before { do_something }
subject { described_class.new(params) }
it { expect_something }
subject { described_class.new(params) }
it { expect_something_else }
# good
subject { described_class.new(params) }
let(:params) { blah }
# good
subject { described_class.new(params) }
before { do_something }
# good
subject { described_class.new(params) }
it { expect_something }
it { expect_something_else }
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.35 |
- |
Checks that no class, module, or constant is declared.
Constants, including classes and modules, when declared in a block scope, are defined in global namespace, and leak between examples.
If several examples may define a DummyClass
, instead of being a
blank slate class as it will be in the first example, subsequent
examples will be reopening it and modifying its behavior in
unpredictable ways.
Even worse when a class that exists in the codebase is reopened.
Anonymous classes are fine, since they don’t result in global namespace name clashes.
# bad
describe SomeClass do
OtherClass = Struct.new
CONSTANT_HERE = 'I leak into global namespace'
end
# good
describe SomeClass do
before do
stub_const('OtherClass', Struct.new)
stub_const('CONSTANT_HERE', 'I only exist during this example')
end
end
# bad
describe SomeClass do
class FooClass < described_class
def double_that
some_base_method * 2
end
end
it { expect(FooClass.new.double_that).to eq(4) }
end
# good - anonymous class, no constant needs to be defined
describe SomeClass do
let(:foo_class) do
Class.new(described_class) do
def double_that
some_base_method * 2
end
end
end
it { expect(foo_class.new.double_that).to eq(4) }
end
# good - constant is stubbed
describe SomeClass do
before do
foo_class = Class.new(described_class) do
def do_something
end
end
stub_const('FooClass', foo_class)
end
it { expect(FooClass.new.double_that).to eq(4) }
end
# bad
describe SomeClass do
module SomeModule
class SomeClass
def do_something
end
end
end
end
# good
describe SomeClass do
before do
foo_class = Class.new(described_class) do
def do_something
end
end
stub_const('SomeModule::SomeClass', foo_class)
end
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.16 |
1.22 |
Checks for let
definitions that come after an example.
# bad
let(:foo) { bar }
it 'checks what foo does' do
expect(foo).to be
end
let(:some) { other }
it 'checks what some does' do
expect(some).to be
end
# good
let(:foo) { bar }
let(:some) { other }
it 'checks what foo does' do
expect(foo).to be
end
it 'checks what some does' do
expect(some).to be
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.7 |
- |
Checks unreferenced let!
calls being used for test setup.
# bad
let!(:my_widget) { create(:widget) }
it 'counts widgets' do
expect(Widget.count).to eq(1)
end
# good
it 'counts widgets' do
create(:widget)
expect(Widget.count).to eq(1)
end
# good
before { create(:widget) }
it 'counts widgets' do
expect(Widget.count).to eq(1)
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
Yes |
2.19 |
- |
Checks where match_array
is used.
This cop checks for the following:
- Prefer contain_exactly
when matching an array with values.
- Prefer eq
when using match_array
with an empty array literal.
# bad
it { is_expected.to match_array([content1, content2]) }
# good
it { is_expected.to contain_exactly(content1, content2) }
# good
it { is_expected.to match_array([content] + array) }
# good
it { is_expected.to match_array(%w(tremble in fear foolish mortals)) }
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.7 |
- |
Check that chains of messages are not being stubbed.
# bad
allow(foo).to receive_message_chain(:bar, :baz).and_return(42)
# good
thing = Thing.new(baz: 42)
allow(foo).to receive(:bar).and_return(thing)
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Disabled |
Yes |
No |
1.7 |
1.8 |
Checks for consistent message expectation style.
This cop can be configured in your configuration using the
EnforcedStyle
option and supports --auto-gen-config
.
# bad
expect(foo).to receive(:bar)
# good
allow(foo).to receive(:bar)
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.9 |
- |
Checks that message expectations are set using spies.
This cop can be configured in your configuration using the
EnforcedStyle
option and supports --auto-gen-config
.
# bad
expect(foo).to receive(:bar)
do_something
# good
allow(foo).to receive(:bar) # or use instance_spy
do_something
expect(foo).to have_received(:bar)
Name | Default value | Configurable values |
---|---|---|
EnforcedStyle |
|
|
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
Yes |
2.24 |
- |
Use consistent metadata style.
This cop does not support autocorrection in the case of
EnforcedStyle: hash
where the trailing metadata type is ambiguous.
(e.g. describe 'Something', :a, b
)
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.28 |
- |
Checks that the first argument to an example group is not empty.
# bad
describe do
end
RSpec.describe do
end
# good
describe TestedClass do
end
describe "A feature example" do
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.0 |
- |
Checks for multiple top-level example groups.
Multiple descriptions for the same class or module should either be nested or separated into different test files.
# bad
describe MyClass, '.do_something' do
end
describe MyClass, '.do_something_else' do
end
# good
describe MyClass do
describe '.do_something' do
end
describe '.do_something_else' do
end
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.7 |
1.21 |
Checks if examples contain too many expect
calls.
This cop is configurable using the Max
option
and works with --auto-gen-config
.
# bad
describe UserCreator do
it 'builds a user' do
expect(user.name).to eq("John")
expect(user.age).to eq(22)
end
end
# good
describe UserCreator do
it 'sets the users name' do
expect(user.name).to eq("John")
end
it 'sets the users age' do
expect(user.age).to eq(22)
end
end
# good - the cop ignores when RSpec aggregates failures
describe UserCreator do
it 'builds a user', :aggregate_failures do
expect(user.name).to eq("John")
expect(user.age).to eq(22)
end
end
# Detected as an offense
describe UserCreator do
it 'builds a user', aggregate_failures: false do
expect(user.name).to eq("John")
expect(user.age).to eq(22)
end
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.43 |
- |
Checks if example groups contain too many let
and subject
calls.
This cop is configurable using the Max
option and the AllowSubject
which will configure the cop to only register offenses on calls to
let
and not calls to subject
.
# bad
describe MyClass do
let(:foo) { [] }
let(:bar) { [] }
let!(:baz) { [] }
let(:qux) { [] }
let(:quux) { [] }
let(:quuz) { {} }
end
describe MyClass do
let(:foo) { [] }
let(:bar) { [] }
let!(:baz) { [] }
context 'when stuff' do
let(:qux) { [] }
let(:quux) { [] }
let(:quuz) { {} }
end
end
# good
describe MyClass do
let(:bar) { [] }
let!(:baz) { [] }
let(:qux) { [] }
let(:quux) { [] }
let(:quuz) { {} }
end
describe MyClass do
context 'when stuff' do
let(:foo) { [] }
let(:bar) { [] }
let!(:booger) { [] }
end
context 'when other stuff' do
let(:qux) { [] }
let(:quux) { [] }
let(:quuz) { {} }
end
end
# rubocop.yml
# RSpec/MultipleMemoizedHelpers:
# AllowSubject: false
# bad - `subject` counts towards memoized helpers
describe MyClass do
subject { {} }
let(:foo) { [] }
let(:bar) { [] }
let!(:baz) { [] }
let(:qux) { [] }
let(:quux) { [] }
end
Name | Default value | Configurable values |
---|---|---|
AllowSubject |
|
Boolean |
Max |
|
Integer |
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.16 |
- |
Checks if an example group defines subject
multiple times.
This cop does not support autocorrection in some cases. The autocorrect behavior for this cop depends on the type of duplication:
-
If multiple named subjects are defined then this probably indicates that the overwritten subjects (all subjects except the last definition) are effectively being used to define helpers. In this case they are replaced with
let
. -
If multiple unnamed subjects are defined though then this can only be dead code and we remove the overwritten subject definitions.
-
If subjects are defined with
subject!
then we don’t autocorrect. This is enough of an edge case that people can just move this to abefore
hook on their own
# bad
describe Foo do
subject(:user) { User.new }
subject(:post) { Post.new }
end
# good
describe Foo do
let(:user) { User.new }
subject(:post) { Post.new }
end
# bad (does not support autocorrection)
describe Foo do
subject!(:user) { User.new }
subject!(:post) { Post.new }
end
# good
describe Foo do
before do
User.new
Post.new
end
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.5.3 |
2.15 |
Checks for explicitly referenced test subjects.
RSpec lets you declare an "implicit subject" using subject { … }
which allows for tests like it { is_expected.to be_valid }
.
If you need to reference your test subject you should explicitly
name it using subject(:your_subject_name) { … }
. Your test subjects
should be the most important object in your tests so they deserve
a descriptive name.
This cop can be configured in your configuration using EnforcedStyle
,
and IgnoreSharedExamples
which will not report offenses for implicit
subjects in shared example groups.
# bad
RSpec.describe User do
subject { described_class.new }
it 'is valid' do
expect(subject.valid?).to be(true)
end
end
# good
RSpec.describe User do
subject(:user) { described_class.new }
it 'is valid' do
expect(user.valid?).to be(true)
end
end
# also good
RSpec.describe User do
subject(:user) { described_class.new }
it { is_expected.to be_valid }
end
# bad
RSpec.describe User do
subject(:user) { described_class.new }
it 'is valid' do
expect(subject.valid?).to be(true)
end
end
# good
RSpec.describe User do
subject(:user) { described_class.new }
it 'is valid' do
expect(user.valid?).to be(true)
end
end
# also good
RSpec.describe User do
subject { described_class.new }
it { is_expected.to be_valid }
end
# acceptable
RSpec.describe User do
subject { described_class.new }
it 'is valid' do
expect(subject.valid?).to be(true)
end
end
Name | Default value | Configurable values |
---|---|---|
EnforcedStyle |
|
|
IgnoreSharedExamples |
|
Boolean |
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.7 |
2.13 |
Checks for nested example groups.
This cop is configurable using the Max
option
and supports --auto-gen-config
.
# bad
context 'when using some feature' do
let(:some) { :various }
let(:feature) { :setup }
context 'when user is signed in' do # flagged by rubocop
let(:user) do
UserCreate.call(user_attributes)
end
let(:user_attributes) do
{
name: 'John',
age: 22,
role: role
}
end
context 'when user is an admin' do # flagged by rubocop
let(:role) { 'admin' }
it 'blah blah'
it 'yada yada'
end
end
end
# good
context 'using some feature as an admin' do
let(:some) { :various }
let(:feature) { :setup }
let(:user) do
UserCreate.call(
name: 'John',
age: 22,
role: 'admin'
)
end
it 'blah blah'
it 'yada yada'
end
# bad
describe Foo do
context 'foo' do
context 'bar' do
context 'baz' do # flagged by rubocop
end
end
end
end
# bad
describe Foo do
context 'foo' do
context 'bar' do # flagged by rubocop
context 'baz' do # flagged by rubocop
end
end
end
end
describe Foo do # <-- nested groups 1
context 'foo' do # <-- nested groups 2
context 'bar' do # <-- nested groups 3
end
end
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
No |
No |
2.13 |
2.14 |
Checks if an example contains any expectation.
All RSpec’s example and expectation methods are covered by default. If you are using your own custom methods, add the following configuration:
RSpec: Language: Examples: Regular: - custom_it Expectations: - custom_expect
This cop can be customized with an allowed expectation methods pattern
with an AllowedPatterns
option. ^expect_ and ^assert_ are allowed
by default.
# bad
it do
a?
end
# good
it do
expect(a?).to be(true)
end
Name | Default value | Configurable values |
---|---|---|
AllowedPatterns |
|
Array |
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.4 |
- |
Checks for consistent method usage for negating expectations.
# bad
it '...' do
expect(false).to_not be_true
end
# good
it '...' do
expect(false).not_to be_true
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.14 |
- |
Checks if there is a let/subject that overwrites an existing one.
# bad
let(:foo) { bar }
let(:foo) { baz }
subject(:foo) { bar }
let(:foo) { baz }
let(:foo) { bar }
let!(:foo) { baz }
# good
subject(:test) { something }
let(:foo) { bar }
let(:baz) { baz }
let!(:other) { other }
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Disabled |
Yes |
No |
1.25 |
- |
Checks for any pending or skipped examples.
# bad
describe MyClass do
it "should be true"
end
describe MyClass do
it "should be true", skip: true do
expect(1).to eq(2)
end
end
describe MyClass do
it "should be true" do
pending
end
end
describe MyClass do
xit "should be true" do
end
end
# good
describe MyClass do
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
No |
2.16 |
- |
Checks for pending or skipped examples without reason.
# bad
pending 'does something' do
end
# bad
it 'does something', :pending do
end
# bad
it 'does something' do
pending
end
# bad
xdescribe 'something' do
end
# bad
skip 'does something' do
end
# bad
it 'does something', :skip do
end
# bad
it 'does something' do
skip
end
# bad
it 'does something'
# good
it 'does something' do
pending 'reason'
end
# good
it 'does something' do
skip 'reason'
end
# good
it 'does something', pending: 'reason' do
end
# good
it 'does something', skip: 'reason' do
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes (Unsafe) |
1.16 |
- |
Prefer using predicate matcher over using predicate method directly.
RSpec defines magic matchers for predicate methods. This cop recommends to use the predicate matcher instead of using predicate method directly.
# bad
expect(foo.something?).to be_truthy
# good
expect(foo).to be_something
# also good - It checks "true" strictly.
expect(foo.something?).to be(true)
# bad
expect(foo.something?).to be_truthy
expect(foo.something?).to be(true)
# good
expect(foo).to be_something
# bad
expect(foo).to be_something
# good - the above code is rewritten to it by this cop
expect(foo.something?).to be(true)
# bad - no autocorrect
expect(foo)
.to be_something(<<~TEXT)
bar
TEXT
# good
expect(foo.something?(<<~TEXT)).to be(true)
bar
TEXT
Name | Default value | Configurable values |
---|---|---|
Strict |
|
Boolean |
EnforcedStyle |
|
|
AllowedExplicitMatchers |
|
Array |
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.26 |
- |
Check for once
and twice
receive counts matchers usage.
# bad
expect(foo).to receive(:bar).exactly(1).times
expect(foo).to receive(:bar).exactly(2).times
expect(foo).to receive(:bar).at_least(1).times
expect(foo).to receive(:bar).at_least(2).times
expect(foo).to receive(:bar).at_most(1).times
expect(foo).to receive(:bar).at_most(2).times
# good
expect(foo).to receive(:bar).once
expect(foo).to receive(:bar).twice
expect(foo).to receive(:bar).at_least(:once)
expect(foo).to receive(:bar).at_least(:twice)
expect(foo).to receive(:bar).at_most(:once)
expect(foo).to receive(:bar).at_most(:twice).times
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
Yes (Unsafe) |
2.23 |
- |
Checks for multiple messages stubbed on the same object.
The autocorrection is marked as unsafe, because it may change the order of stubs. This in turn may cause e.g. variables to be called before they are defined.
# bad
before do
allow(Service).to receive(:foo).and_return(bar)
allow(Service).to receive(:baz).and_return(qux)
end
# good
before do
allow(Service).to receive_messages(foo: bar, baz: qux)
end
# good - ignore same message
before do
allow(Service).to receive(:foo).and_return(bar)
allow(Service).to receive(:foo).and_return(qux)
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.28 |
- |
Prefer not_to receive(…)
over receive(…).never
.
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
Yes |
2.19 |
- |
Remove redundant around
hook.
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.9 |
- |
Check for repeated description strings in example groups.
# bad
RSpec.describe User do
it 'is valid' do
# ...
end
it 'is valid' do
# ...
end
end
# good
RSpec.describe User do
it 'is valid when first and last name are present' do
# ...
end
it 'is valid when last name only is present' do
# ...
end
end
# good
RSpec.describe User do
it 'is valid' do
# ...
end
it 'is valid', :flag do
# ...
end
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.10 |
- |
Check for repeated examples within example groups.
it 'is valid' do
expect(user).to be_valid
end
it 'validates the user' do
expect(user).to be_valid
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.38 |
- |
Check for repeated describe and context block body.
# bad
describe 'cool feature x' do
it { cool_predicate }
end
describe 'cool feature y' do
it { cool_predicate }
end
# good
describe 'cool feature' do
it { cool_predicate }
end
describe 'another cool feature' do
it { another_predicate }
end
# good
context 'when case x', :tag do
it { cool_predicate }
end
context 'when case y' do
it { cool_predicate }
end
# good
context Array do
it { is_expected.to respond_to :each }
end
context Hash do
it { is_expected.to respond_to :each }
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.38 |
- |
Check for repeated example group descriptions.
# bad
describe 'cool feature' do
# example group
end
describe 'cool feature' do
# example group
end
# bad
context 'when case x' do
# example group
end
describe 'when case x' do
# example group
end
# good
describe 'cool feature' do
# example group
end
describe 'another cool feature' do
# example group
end
# good
context 'when case x' do
# example group
end
context 'when another case' do
# example group
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.44 |
- |
Check for repeated include of shared examples.
# bad
describe 'foo' do
include_examples 'cool stuff'
include_examples 'cool stuff'
end
# bad
describe 'foo' do
it_behaves_like 'a cool', 'thing'
it_behaves_like 'a cool', 'thing'
end
# bad
context 'foo' do
it_should_behave_like 'a duck'
it_should_behave_like 'a duck'
end
# good
describe 'foo' do
include_examples 'cool stuff'
end
describe 'bar' do
include_examples 'cool stuff'
end
# good
describe 'foo' do
it_behaves_like 'a cool', 'thing'
it_behaves_like 'a cool', 'person'
end
# good
context 'foo' do
it_should_behave_like 'a duck'
it_should_behave_like 'a goose'
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.16 |
1.22 |
Checks for consistent style of stub’s return setting.
Enforces either and_return
or block-style return in the cases
where the returned value is constant. Ignores dynamic returned values
are the result would be different
This cop can be configured using the EnforcedStyle
option
# bad
allow(Foo).to receive(:bar) { "baz" }
expect(Foo).to receive(:bar) { "baz" }
# good
allow(Foo).to receive(:bar).and_return("baz")
expect(Foo).to receive(:bar).and_return("baz")
# also good as the returned value is dynamic
allow(Foo).to receive(:bar) { bar.baz }
Name | Default value | Configurable values |
---|---|---|
EnforcedStyle |
|
|
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.14 |
1.39 |
Checks for let scattered across the example group.
Group lets together
# bad
describe Foo do
let(:foo) { 1 }
subject { Foo }
let(:bar) { 2 }
before { prepare }
let!(:baz) { 3 }
end
# good
describe Foo do
subject { Foo }
before { prepare }
let(:foo) { 1 }
let(:bar) { 2 }
let!(:baz) { 3 }
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.10 |
- |
Checks for setup scattered across multiple hooks in an example group.
Unify before
, after
, and around
hooks when possible.
# bad
describe Foo do
before { setup1 }
before { setup2 }
end
# good
describe Foo do
before do
setup1
setup2
end
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.13 |
- |
Checks for proper shared_context and shared_examples usage.
If there are no examples defined, use shared_context. If there is no setup defined, use shared_examples.
# bad
RSpec.shared_context 'only examples here' do
it 'does x' do
end
it 'does y' do
end
end
# good
RSpec.shared_examples 'only examples here' do
it 'does x' do
end
it 'does y' do
end
end
# bad
RSpec.shared_examples 'only setup here' do
subject(:foo) { :bar }
let(:baz) { :bazz }
before do
something
end
end
# good
RSpec.shared_context 'only setup here' do
subject(:foo) { :bar }
let(:baz) { :bazz }
before do
something
end
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.25 |
- |
Enforces use of string to titleize shared examples.
# bad
it_behaves_like :foo_bar_baz
it_should_behave_like :foo_bar_baz
shared_examples :foo_bar_baz
shared_examples_for :foo_bar_baz
include_examples :foo_bar_baz
# good
it_behaves_like 'foo bar baz'
it_should_behave_like 'foo bar baz'
shared_examples 'foo bar baz'
shared_examples_for 'foo bar baz'
include_examples 'foo bar baz'
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.9 |
1.10 |
Checks that chains of messages contain more than one element.
# bad
allow(foo).to receive_message_chain(:bar).and_return(42)
# good
allow(foo).to receive(:bar).and_return(42)
# also good
allow(foo).to receive(:bar, :baz)
allow(foo).to receive("bar.baz")
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
No |
2.19 |
- |
Checks for passing a block to skip
within examples.
# bad
it 'does something' do
skip 'not yet implemented' do
do_something
end
end
# good
it 'does something' do
skip 'not yet implemented'
do_something
end
# good - when outside example
skip 'not yet implemented' do
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
Yes |
2.14 |
- |
Sort RSpec metadata alphabetically.
# bad
describe 'Something', :b, :a
context 'Something', foo: 'bar', baz: true
it 'works', :b, :a, foo: 'bar', baz: true
# good
describe 'Something', :a, :b
context 'Something', baz: true, foo: 'bar'
it 'works', :a, :b, baz: true, foo: 'bar'
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
No |
2.24 |
- |
Checks that spec file paths are consistent and well-formed.
# bad
whatever_spec.rb # describe MyClass
my_class_spec.rb # describe MyClass, '#method'
# good
my_class_spec.rb # describe MyClass
my_class_method_spec.rb # describe MyClass, '#method'
my_class/method_spec.rb # describe MyClass, '#method'
# good
rubocop_spec.rb # describe RuboCop
rspec_spec.rb # describe RSpec
Name | Default value | Configurable values |
---|---|---|
Include |
|
Array |
Exclude |
|
Array |
CustomTransform |
|
|
IgnoreMethods |
|
Boolean |
IgnoreMetadata |
|
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
No |
2.24 |
- |
Checks that spec file paths suffix are consistent and well-formed.
# bad
my_class/foo_specorb.rb # describe MyClass
spec/models/user.rb # describe User
spec/models/user_specxrb # describe User
# good
my_class_spec.rb # describe MyClass
# good - shared examples are allowed
spec/models/user.rb # shared_examples_for 'foo'
Name | Default value | Configurable values |
---|---|---|
Include |
|
Array |
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.44 |
- |
Checks that message expectations do not have a configured response.
# bad
expect(foo).to receive(:bar).with(42).and_return("hello world")
# good (without spies)
allow(foo).to receive(:bar).with(42).and_return("hello world")
expect(foo).to receive(:bar).with(42)
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
No |
2.5 |
- |
Ensure that subject is defined using subject helper.
# bad
let(:subject) { foo }
let!(:subject) { foo }
subject(:subject) { foo }
subject!(:subject) { foo }
# bad
block = -> {}
let(:subject, &block)
# good
subject(:test_subject) { foo }
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.7 |
2.8 |
Checks for stubbed test subjects.
Checks nested subject stubs for innermost subject definition when subject is also defined in parent example groups.
# bad
describe Article do
subject(:article) { Article.new }
it 'indicates that the author is unknown' do
allow(article).to receive(:author).and_return(nil)
expect(article.description).to include('by an unknown author')
end
end
# bad
describe Article do
subject(:foo) { Article.new }
context 'nested subject' do
subject(:article) { Article.new }
it 'indicates that the author is unknown' do
allow(article).to receive(:author).and_return(nil)
expect(article.description).to include('by an unknown author')
end
end
end
# good
describe Article do
subject(:article) { Article.new(author: nil) }
it 'indicates that the author is unknown' do
expect(article.description).to include('by an unknown author')
end
end
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.30 |
- |
Checks for a specified error in checking raised errors.
Enforces one of an Exception type, a string, or a regular
expression to match against the exception message as a parameter
to raise_error
# bad
expect {
raise StandardError.new('error')
}.to raise_error
# good
expect {
raise StandardError.new('error')
}.to raise_error(StandardError)
expect {
raise StandardError.new('error')
}.to raise_error('error')
expect {
raise StandardError.new('error')
}.to raise_error(/err/)
expect { do_something }.not_to raise_error
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.40 |
- |
Checks that memoized helpers names are symbols or strings.
# bad
subject('user') { create_user }
let('user_name') { 'Adam' }
# good
subject(:user) { create_user }
let(:user_name) { 'Adam' }
Name | Default value | Configurable values |
---|---|---|
EnforcedStyle |
|
|
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.40 |
2.13 |
Checks that memoized helper names use the configured style.
Variables can be excluded from checking using the AllowedPatterns
option.
# bad
subject(:userName1) { 'Adam' }
let(:userName2) { 'Adam' }
# good
subject(:user_name_1) { 'Adam' }
let(:user_name_2) { 'Adam' }
# bad
subject(:user_name_1) { 'Adam' }
let(:user_name_2) { 'Adam' }
# good
subject(:userName1) { 'Adam' }
let(:userName2) { 'Adam' }
Name | Default value | Configurable values |
---|---|---|
EnforcedStyle |
|
|
AllowedPatterns |
|
Array |
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Pending |
Yes |
Yes (Unsafe) |
2.10.0 |
2.12 |
Checks for consistent verified double reference style.
Only investigates references that are one of the supported styles.
This cop can be configured in your configuration using the
EnforcedStyle
option and supports --auto-gen-config
.
# bad
let(:foo) do
instance_double('ClassName', method_name: 'returned_value')
end
# good
let(:foo) do
instance_double(ClassName, method_name: 'returned_value')
end
# bad
let(:foo) do
instance_double(ClassName, method_name: 'returned_value')
end
# good
let(:foo) do
instance_double('ClassName', method_name: 'returned_value')
end
Name | Default value | Configurable values |
---|---|---|
EnforcedStyle |
|
|
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.2.1 |
1.5 |
Prefer using verifying doubles over normal doubles.
# bad
let(:foo) do
double(method_name: 'returned value')
end
# bad
let(:foo) do
double("ClassName", method_name: 'returned value')
end
# good
let(:foo) do
instance_double("ClassName", method_name: 'returned value')
end
Name | Default value | Configurable values |
---|---|---|
IgnoreNameless |
|
Boolean |
IgnoreSymbolicNames |
|
Boolean |
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
No |
1.16 |
- |
Checks void expect()
.
Enabled by default | Safe | Supports autocorrection | Version Added | Version Changed |
---|---|---|---|---|
Enabled |
Yes |
Yes |
1.32 |
- |
Checks for calling a block within a stub.
# bad
allow(foo).to receive(:bar) { |&block| block.call(1) }
# good
expect(foo).to receive(:bar).and_yield(1)